Two phase ball expansion valve for heat pump

Abstract

A device for expansion of coolant having a housing with a flow channel. A ball-shaped valve element arranged to be integrated inside the housing. The valve element is mounted so that it can turn about an axis of rotation and is configured with a through channel. The through channel of the valve element is configured with an entry opening and an exit opening and arranged so that the flow cross section of the through channel decreases from the entry opening to the exit opening in the direction of flow of the coolant. At the exit of the through channel the least flow cross section is formed.

What is claimed is: 
     
       1. A device for expansion of a coolant, the device comprising:
 a housing with a flow channel formed therein, the flow channel including a first segment having a first cross-sectional flow area and a second segment having a second cross-sectional flow area, wherein the first cross-sectional flow area is substantially equal to the second cross-sectional flow area; and 
 a ball-shaped valve element disposed in the housing intermediate the first cross-sectional flow area of the first segment of the flow channel and the second cross-sectional flow area of the second segment of the flow channel and configured to rotate about an axis of rotation, the valve element having a through channel formed therein configured for selective fluid communication with the flow channel of the housing, the through channel including an entry opening having a third cross-sectional flow area and an exit opening having a fourth cross-sectional flow area smaller than the third cross-sectional flow area, wherein the third cross-sectional flow area of the entry opening is larger than each of the first cross-sectional flow area of the first segment of the flow channel and the second cross-sectional flow area of the second segment of the flow channel, and wherein the fourth cross-sectional flow area of the exit opening is smaller than each of the first cross-sectional flow area of the first segment of the flow channel and the second cross-sectional flow area of the second segment of the flow channel, wherein the valve element is continuously adjustable in intermediate positions between a first fully opened end position, a fully closed position, and a second fully opened end position, and wherein the valve element is turned by 180° between the first fully opened end position and the second fully opened end position, wherein a first overlap present between the third cross-sectional flow area of the entry opening and one of the first cross-sectional flow area of the first segment of the flow channel and the second cross-sectional flow area of the second segment of the flow channel remains constant when the valve element is rotated through a first range of rotational positions and wherein a second overlap present between the fourth cross-sectional flow area of the exit opening and an other of the first cross-sectional flow area of the first segment of the flow channel and the second cross-sectional flow area of the second segment of the flow channel remains constant when the valve element is rotated through the first range of rotational positions, and wherein the first overlap and the second overlap establish the selective fluid communication between the through channel of the valve element and the flow channel of the housing. 
 
     
     
       2. The device according to  claim 1 , wherein the through channel of the valve element has a substantially conical shape. 
     
     
       3. The device according to  claim 1 , wherein the through channel of the valve element has a shape of a truncated cone. 
     
     
       4. The device according to  claim 3 , wherein the through channel of the valve element has the shape of a straight truncated cone. 
     
     
       5. The device according to  claim 1 , wherein the through channel is bounded by a surface of rotation which is formed by rotation of a line about an axis of symmetry to create a substantially circular flow cross section which reduces substantially uniformly from the entry opening with a larger diameter than the exit opening. 
     
     
       6. The device according to  claim 1 , wherein a diameter of the entry opening of the through channel is larger than a diameter of the flow channel of the housing. 
     
     
       7. The device according to  claim 1 , wherein a diameter of the entry opening of the through channel substantially equal to a diameter of the flow channel of the housing. 
     
     
       8. The device according to  claim 1 , wherein a diameter of the exit opening of the through channel is smaller than a diameter of the flow channel of the housing. 
     
     
       9. The device according to  claim 1 , wherein a transition zone at the entry opening to the through channel of the valve element between a surface forming the through channel and an outer surface of the valve element is rounded. 
     
     
       10. The device according to  claim 1 , wherein a first 90° turn adjusts the valve element between the first fully opened end position and the fully closed position and wherein a second 90° turn adjusts the valve element between the second fully opened end position and the fully closed position. 
     
     
       11. The device according to  claim 1 , wherein the valve element is configured to receive a bidirectional flow of the coolant therethrough. 
     
     
       12. A device for expansion of a coolant, the device comprising:
 a housing with a flow channel formed therein, the flow channel including a first segment having a first cross-sectional flow area and a second segment having a second cross-sectional flow area, wherein the first cross-sectional flow area is substantially equal to the second cross-sectional flow area; and 
 a ball-shaped valve element disposed in the housing intermediate the first cross-sectional flow area of the first segment of the flow channel and the second cross-sectional flow area of the second segment of the flow channel and configured to rotate about an axis of rotation, the valve element having a through channel formed therein configured for selective fluid communication with the flow channel of the housing, the through channel including an entry opening having a third cross-sectional flow area and an exit opening having a fourth cross-sectional flow area smaller than the third cross-sectional flow area, a diameter of the entry opening of the through channel larger than a diameter of each of the first segment and the second segment of the flow channel of the housing and a diameter of the exit opening of the through channel smaller than the diameter of each of the first segment and the second segment of the flow channel of the housing, wherein the valve element is continuously adjustable in intermediate positions between a first fully opened end position, a fully closed position, and a second fully opened end position, and wherein the valve element is turned by 180° between the first fully opened end position and the second fully opened end position, wherein a first overlap present between the third cross-sectional flow area of the entry opening and one of the first cross-sectional flow area of the first segment of the flow channel and the second cross-sectional flow area of the second segment of the flow channel remains constant when the valve element is rotated through a first range of rotational positions and wherein a second overlap present between the fourth cross-sectional flow area of the exit opening and an other of the first cross-sectional flow area of the first segment of the flow channel and the second cross-sectional flow area of the second segment of the flow channel remains constant when the valve element is rotated through the first range of rotational positions, wherein the first overlap and the second overlap establish the selective fluid communication between the through channel of the valve element and the flow channel of the housing. 
 
     
     
       13. The device according to  claim 12 , wherein the through channel of the valve element has a substantially conical shape. 
     
     
       14. The device according to  claim 12 , wherein a transition zone at the entry opening to the through channel of the valve element between a surface forming the through channel and an outer surface of the valve element is rounded. 
     
     
       15. The device according to  claim 12 , wherein a first 90° turn adjusts the valve element between the first fully opened end position and the fully closed position and wherein a second 90° turn adjusts the valve element between the second fully opened end position and the fully closed position. 
     
     
       16. The device according to  claim 12 , wherein the valve element is configured to receive a bidirectional flow of the coolant therethrough.